If you have seed to spare of Walter, I'll have a go at waking them up. Alternately, Have a look at the role of oxygen in seed germination, particularly old seed or seed with hard coats can benefit from the use of hydrogen peroxide and the free oxygen released when it degrades.
worth a try if you have lots of seeds as trying the same technique repeatedly hasn't worked so far.
KarenO
http://tomatoville.com/showthread.php?t=43931